Wednesday, August 17, 2016

Load Testing Tools for IoT platforms over MQTT

While IoT platforms can be tested using traditional load testing tools if standard protocols such as HTTP are used, there are a suite of other tools that can be used if you need to test the MQTT throughput capacity of your IoT platforms.

Jotting down a list of tools that can be used to test the MQTT broker of IoT platforms.

Thursday, August 11, 2016

Ruminating on MQTT

MQTT is a lightweight messaging protocol over TCP/IP that supports the publish-subscribe paradigm. It is most suited for low bandwidth / high latency and unreliable networks and hence is a natural fit for field IoT devices.  A good MQTT primer is available here.

MQTT was the de-facto protocol for all our IoT applications, but of late we have started experimenting with MQTT even for mobile apps, after we learned that Facebook Messenger app uses MQTT :)

MQTT sessions can survive across TCP connection re-connects and thus is very useful in unreliable network conditions. Also in MQTT, you can specify the QoS level - e.g.
  • Fire and forget (QoS 0)
  • At least once (QoS 1)
  • Exactly once (QoS 2)
It is very important to check if the MQTT broker we choose supports the required QoS levels. 
MQTT supports a hierarchy of topics, so you can subscribe to a top level topic and get all the messages to the subscriber. 

Most of the popular open source message brokers such as ActiveMQ, RabbitMQ and HiveMQ already support MQTT. A good comparison of the various MQTT brokers is available here -

A performance benchmark of MQTT brokers is available here -